Help, trouble getting intimate?!?

My boyfriend and I have been dating for about 7 months an are 17 and 18 years old, and recently we've been getting a little more intimate while making out. We don't plan on having sex, but a little feeling and exploring has been happening. For some reasons, he's getting more out of touching me than i am. Though we can joke about how i don't feel turned on when he touches my breasts, it's caused us some problems. We are both good to one another and do not blame each other, but I need help figuring out what I am suppose to do, he is pretty much my first boyfriend. I really want to be able to go there with him and I know it's hurting him and it's on his mind. He's tried to touch me down there but only when my pants are on...he's even tried my butt and I feel nothing. I enjoy kissing him and having him kiss my neck, but it's not enough..help?!